The overall goal of this proposal is to develop a prototype system for high performance two-dimensional strain rate imaging (SRI) of the heart and assess its ability to provide noninvasive regional quantification of diastolic function. Current SRI implementations compromise image quality because simple tissue Doppler processing must be used to maintain real-time frame rates. High performance SRI with greatly reduced angle dependent artifacts requires a two-dimensional complex correlation computation at every pixel within a frame of a 200Hz ultrasound imaging sequence. In addition, simultaneous real-time display of tissue strain images and "trashograms" can provide valuable feedback information. Using these real-time displays, an echocardiographer can maximize the signal to noise ratio of SRI while simultaneously minimizing artifacts due to out-of-plane motion. Real-time computation of these images is beyond the state-of-the-art for current scanners, even those high performance machines using complex correlation for free hand, three dimensional scanning. Pixel Velocity Inc. in collaboration with the Biomedical Ultrasonics Lab at the University of Michigan, has validated the feasibility of implementing a practical real-time two-dimensional correlation processor with all these capabilities during the Phase I grant. The result of a Phase II grant will be a real-time system integrating Pixel Velocity's two-dimensional correlation processor with a WmProbe Corp. highly parallel beamformer, specifically optimized for high frame rate, two-dimensional strain rate imaging of the heart. No commercial system has the equivalent mix of beam forming and signal processing capabilities to test the clinical significance of real-time, multi-dimensional strain rate imaging.